And I guess that I shouldn't even tell her i am not interested, I juste need to not answer anything?
Yes, if you are hoping to have her move on out of your life, if that's where it's at...
Personally, presumably like you and most others, I would rather make peace with someone, set things to rest, live and let live, and love, agape style. But this isn't always possible. Always remember that negative attention is attention, although most of us - HPDs and Nons alike - prefer positive attention. I think some HPDs will settle for 99% negative attention, especially if it culminates in some way in 1% positive attention...even if it means they must take on the role of the annoying pesky bad girl or boy, that insufferable so and so that's in your life. So if this is the unfortunate situation you find yourself in, no attention will be the surest way to get her or him to move on (and who knows, maybe they might even become self-aware and take a swing at recovery?)
Sometimes when everything is mulled over, sifted, and carefully considered, there is this undeniable moment that presents itself, that things are definitively over, and the best peace is achieved by moving along. Don't hesitate to seize that moment, if in fact that's where you and her are at.